.- I have a pool of MDBs receiving messages from a JMS Queue..- Each MDB uses a Stateless Session Bean (which is the session facade for several BMP-Entity Beans) from a pool to populate info in the DB [SQL Server 2000].

.- If I use a Singleton MDB (basically setting the size of the MDB pool to 1), everything works fine..- If I use a pool of MDB I always get a Deadlock exception at DB level.

I am not sure if the problem is in the MDB or in the Entity Beans... I have tried to use other configurations for the EBs like "Instance Per Transaction BMP EntityBean" but it still doesn't work. I have also specified read-only methods (when possible) for the EBs.